<?phprequire_once('lib/connects_db.php');class Login_Os {	public function login($user, $pass){		$login_db = new Connect_Db();		$conn_os = $login_db->conn_db();		$hash_pw = $pass;//sha1($pword);    		$query = "SELECT username, password FROM users				  WHERE username ='$user' 				  AND password='$hash_pw' 				  LIMIT 1";		$result = mysqli_query($conn_os,$query) or die(mysqli_error($conn_os));		if(mysqli_num_rows($result) == 1) {			return true;		} else {			return false;		}		return false;	}	}?>